| 摘要 |
PROBLEM TO BE SOLVED: To provide a counter-type scanning optical device configured to stably support an optical box even if an F&thetas; lens is thermally deformed, while enabling color registration.SOLUTION: A counter-type scanning optical device 6 includes first and second optical component groups 50A, 50B arranged symmetrically with respect to a deflector 40. A second F&thetas; lens 52A in the first optical component group 50A is supported on a lower surface 81a of a horizontal downward first frame part 81. A second F&thetas; lens 52B in the second optical component group 50B is supported on a top surface 83a of a horizontal upward second frame part 83. In the optical component groups, the second F&thetas; lenses 52A 52B are thermally deformed in opposite directions in a sub-scanning direction. Because of this, images formed on surfaces of two photoreceptor drums 10 are displaced in the same direction in the sub-scanning direction, thereby enabling color registration in the sub-scanning direction. |
